This invention relates generally to non-volatile ferroelectric memories. More particularly, the present invention relates to voltage boosting circuitry that enables extremely low voltage operation of non-volatile ferroelectric memories.
Non-volatile memories based on ferroelectric materials are becoming increasingly popular due to their advantages over floating-gate non-volatile memory technologies. The primary advantages of ferroelectric nonvolatile memories are low write voltage (less than five volts versus greater than ten volts for competing technologies), fast write time (less than 100 ns versus volts for competing technologies), fast write time (less than 100 ns versus greater than 1 ms) and low power consumption (charge-based read/write versus current-based read/write). Historically, ferroelectric materials have been developed for integrated circuits energized with a five volt power supply. volts for competing technologies), fast write time (less than 100 ns versus In recent years, a large migration has occurred to 3.3 volt system power supplies. While ferroelectric memory manufacturers have worked to develop production worthy three volt materials, more and more designs are now migrating to 1.8 volt supplies and even lower voltage supplies. Current designs using available ferroelectric materials and conventional ferroelectric memory architectures are inoperable using these 1.8 volt systems because there is simply not enough voltage to generate practically detectable amounts of switched charge.
What is desired, therefore, is a circuit design and architecture for a ferroelectric memory that enables reliable low voltage power supply operation (such as 1.8 volt power supply operation) using state-of-the-art 3.3 volt and other higher-voltage compatible ferroelectric materials.